Keystone Electrical Instrument Co. DC Voltmeter

Measures the electric potential difference (voltage) between two points in an electrical circuit. Comes in a wooden box with original label and information on the inside of the lid.

Figure 1: Keystone Electrical Instrument Co. DC Voltmeter

Measures the electric potential difference (voltage) between two points in an electrical circuit. Comes in a wooden box with original label and information on the inside of the lid. Close up of the information on the inside of the lid.

FIgure 2: Keystone Electrical Instrument Co. DC Voltmeter original certification.

Measures the electric potential difference (voltage) between two points in an electrical circuit. Comes in a wooden box with original label and information on the inside of the lid.

Figure 3: Keystone Electrical Instrument Co. DC Voltmeter close up.

Measures the electric potential difference (voltage) between two points in an electrical circuit. Dated 1910.